Substituted phenoxybenzoic acids and derivatives thereof as herbicides

Abstract

2-Nitro-5-(substituted-phenoxy) benzoic acids and esters, salts, amides, and acyl halides thereof comprise a class of compounds that are highly effective herbicides.

What is claimed is: 
     
       1. An herbicidal composition comprising as an effective herbicide, a herbicidally effective quantity of 2-nitro-5-(substituted-phenoxy) benzoic acid, salts thereof selected from the group consisting of lithium salts, sodium salts, potassium salts, alkylammonium salts of 1 to 4 carbon atoms and alkanolammonium salts of 1 to 4 carbon atoms, alkyl esters thereof of 1 to 5 carbon atoms and the phenyl ester thereof, wherein said phenoxy is substituted only by a combination of two members selected from the group consisting of halogen, trifluoromethyl, COOH, ##STR4## alkyl of 1 to 4 carbon atoms), hydroxy, alkoxy of 1 to 4 carbon atoms, ##STR5## SH, SR 1 , SOR 1 , SO 2  R 1 , SO 2  NH 2  wherein R 1  and R 2  are selected from the group consisting of alkyl of 1 to 4 carbon atoms, and an agronomically acceptable carrier selected from the group consisting of solid carriers, water and organic solvents. 
     
     
       2. A composition according to claim 1 wherein said carrier is a solid carrier selected from the group consisting of talc, bentonite, diatomaceous earth, pyropyllite, fullers earth, gypsum, cotton seed flour, nut shell flour, natural clays and synthetic clays, said clays having a pH not exceeding about 9.5. 
     
     
       3. A composition according to claim 1 wherein said carrier is water. 
     
     
       4. A composition according to claim 1 wherein said carrier is an organic solvent. 
     
     
       5. A composition according to claim 1 wherein one member of said combination is halogen. 
     
     
       6. A composition according to claim 5 wherein one member of said combination is trifluoromethyl. 
     
     
       7. A composition according to claim 1 wherein one member of said combination is trifluoromethyl. 
     
     
       8. A method for controlling plant growth which comprises applying a composition consisting essentially of: an herbicidal amount of a compound having the formula: ##STR6## wherein (X) n  is a combination of the members selected from the group consisting of halogen, trifluoromethyl, COOH, ##STR7## (alkyl having 1 to 4 carbon atoms), hydroxy, alkoxy having 1 to 4 carbon atoms, ##STR8## SH, SR 1 , SOR 1 , SO 2  R 1 , SO 2  NH 2  ; R 1  and R 2  are selected from the group consisting of alkyl having 1 to 4 carbon atoms, R is selected from the group consisting of hydroxy, alkoxy having 1 to 5 carbon atoms, and OM wherein M is an alkali metal of lithium, sodium or potassium, alkylammonium having 1 to 4 carbon atoms or alkanolammonium having 1 to 4 carbon atoms and n is the integer 2; and an agronomically acceptable carrier selected from the group consisting of solid carriers, water and organic carriers. 
     
     
       9. A method according to claim 8 wherein an X is trifluoromethyl. 
     
     
       10. A method according to claim 8 which comprises applying said composition to the surface of a growth medium, prior to the emergence of the plants from the growth medium. 
     
     
       11. A method according to claim 8 which comprises applying said composition to plant seedlings after their emergence. 
     
     
       12. A method according to claim 8 which comprises spraying plants with an herbicidally effective amount of said composition. 
     
     
       13. A method according to claim 8 wherein an X is halogen. 
     
     
       14. A method according to claim 13 wherein an X is trifluoromethyl. 
     
     
       15. A method according to claim 8 which comprises applying to plants said compound at a rate of about 0.2 to about 10 pounds per acre.